1. Field of the Invention
The present invention relates to a lawn mower blade stop for use on a rotary lawn mower for use in safely removing and installing lawn mower blades.
2. Brief Description of the Prior Art
The cutting blade of a rotary lawn mower generally comprises a flat elongate member having a cutting edge adjacent each end and on opposite sides. The cutting blade has a center hole and is attached to a shaft by one or more bolts which are threadably received in a bore formed in the end of the shaft or in a fitting keyed to the shaft. As a routine measure in maintaining a rotary lawn mower, it is necessary to remove the blade such that it can be sharpened, straightened or replaced.
In order to securely attach the blade to the shaft, it is necessary to apply a relatively high torque. The same force must be applied when loosening the bolt. The application of such force, causes the blade and the shaft to rotate, which motion must be resisted in order for the bolt to be tightened or loosened. In general the force is too great for an individual to hold the blade with one hand while removing the bolt with the other and the consequences of slipping are serious. Most users block the blade with a piece of wood but the wood tends to fall out when the mower is turned on its side to access the blade. A successful blade stop needs to be inexpensive to manufacture, capable of resisting the high torque applied during blade removal and installation, easy to install without pre-alignment with the blade, etc. While a number of different blade stops which clamp to the blade or to the lawn mower housing have been proposed, none have been entirely satisfactory.